Confluence Free Diagram Plugins: 118 Apps Priced (2026)

Your team is on Confluence Free. Someone installs draw.io, the architecture pages fill up with diagrams, and nobody thinks about it again. Then the eleventh person joins, and the app that cost nothing now costs the whole site $22 a month.

Nothing went wrong. “Free” means three different things in the Marketplace, and most diagram listings only tell you one of them. We pulled every Confluence Cloud diagram app with at least 10 installs from the Marketplace API and priced them all.

Three kinds of free

The “free up to 10 users” tier is the vendor’s choice, not a Marketplace rule. Atlassian gave vendors “the option to set a 1-10 user pricing tier to any price, including $0.00” in December 2021, and most diagram vendors took it. It matches Atlassian’s own Free plan, which has “Seats for up to 10 users”.

What happens at the 11th user follows from how Atlassian bills apps: “Marketplace apps are billed based on the number of users on your site”, and its example is plain: “if you have Confluence Cloud (25 users), you pay the 25-user price for each Marketplace app installed on the app.” You cannot license a diagram app for only the five people who draw.

Two numbers in the chart are worth a second look. Text-to-diagram apps are the most likely to be free outright (15 of 54), because rendering Mermaid or PlantUML needs no storage and little code. Editors are the least likely (6 of 35): a canvas you draw on is real work to build and keep working, and vendors charge for it once you pass 10 users.

Free at any size: editors that draw inside Confluence

Six editors with 10+ installs are free whatever the size of your site. Next to them sits Confluence’s own whiteboard, which is part of every plan.

A few things to know before you pick one:

• The free editor Google shows first is a Connect app. Simple Diagrams tops the results for “confluence free diagram plugin”, and it runs on Atlassian Connect, which reaches end of support on 31 January 2027 (more below).
• The most installed free editor has not shipped since August 2023. Flowchart for Confluence still works on Forge, but a three-year gap is a risk for the diagrams you will keep for years.
• Just Add+ Excalidraw is a companion app. Its listing calls it “a free extension of Just Add+ Embed Markdown, Diagrams, & Code in Confluence Git”, which is a paid app above 10 users. The Excalidraw editor itself is free.
• Whiteboards are not diagrams on a page. They are a separate canvas, good for workshops and planning. On the Free plan each person can keep three active at once.

Free at any size: diagrams written as text

If your diagrams are flowcharts, sequences, class or ER diagrams, writing them as text is the cheapest route at any team size. Fifteen text-to-diagram apps are free outright. The question that separates them is where your text is turned into a picture.

The most installed free diagram app of all is Atlassian’s own. Atlassian Labs’ Mermaid diagrams viewer takes a Mermaid code block that is already on the page and draws it. It asks for no permissions, and if it ever breaks, the source is still on the page as text. It is a viewer, not an editor: you write the Mermaid code in a code block yourself.

The privacy split matters more for PlantUML than for Mermaid. Mermaid is a JavaScript library that draws in the browser. PlantUML is a Java program, so an app has to run it somewhere. The free Instant app uses the public PlantUML server by default, says so openly and lets you point it at your own. If your diagrams describe internal systems, pick an app whose listing says the text stays in Atlassian, or run your own PlantUML server. Our Graphviz guide shows the same question for DOT graphs.

Free app, paid diagrams: connectors

Twenty of the 41 free-at-any-size apps do not draw anything themselves. They show a diagram that lives in another product, and that product has its own price.

These are the right choice when your team already pays for Lucid or Miro: the diagram stays in the tool people know and Confluence shows the live version. They are the wrong choice if you came looking for a free way to draw. Note also where the diagram lives: in the other company’s cloud, not in your Confluence site, so Confluence permissions and exports do not cover it.

What the 11th user costs

For the 57 apps that are free up to 10 users, the bill at 50 users runs from $65 to $1,900 a year. The median is $250 a year at 50 users and $1,330 at 500. Editors cost more than text apps: a median of $340 a year at 50 users against $210.

The two editors most teams install are among the most expensive in the chart: only draw.io’s own Zero Egress edition costs more than draw.io, and nothing costs more than Gliffy. On monthly billing, draw.io charges $2.02 per user a month from 11 to 100 users and Gliffy $3.80. A worked example for an 11-person team on monthly billing:

The same pattern holds for text-to-diagram apps. The most installed ones that are free up to 10 users cost, for 50 users a year: Just Add+ Embed Markdown, Diagrams, & Code $250 (7,946 installs), Mermaid Diagrams for Confluence by Stratus $200 (6,161), PlantUML Diagrams for Confluence by Stratus $350 (5,218), Mermaid Charts & Diagrams by weweave $115 (2,163), Graphviz Diagrams for Confluence by Appfire $600 (609) and ZenUML Diagrams for Confluence $220 (148). If you outgrow a free Mermaid viewer, a paid Mermaid app costs a fraction of a full editor.

Twenty apps charge from the first user, even on a 10-user site. Most are specialist tools, priced for teams that need them: Balsamiq wireframes ($80 a year for 10 users, 2,280 installs), EasyMind mind maps ($55, 1,292) and BPMN Modeler Enterprise ($110, 1,092). Their trials are free; their 10-user tier is not.

Connect apps: check before you build on one

Apps on the Marketplace are built on one of two frameworks. Forge apps run on Atlassian’s platform; Connect apps run on the vendor’s servers, and Atlassian is ending support for them. Its announcement is blunt: “In practice, end of support means ‘use at your own risk.’” Installed apps keep working (“Customers who have Connect apps installed won’t lose access to the app”), but “Only critical or security-related bugs will be addressed.” The end-of-support date was moved to 31 January 2027.

Of the 118 diagram apps, 95 are on Forge and 23 on Connect, with 4,796 installs between them. The Connect ones you are most likely to meet:

A diagram you draw today will be on the page for years. If two apps do the same job, the Forge one is the safer home for it.

Which one to pick

Where our apps fit

We make one of the paid editors, so read this section with that in mind. Our Excalidraw Whiteboard & Mermaid Diagrams for Confluence is free up to 10 users and then the cheapest editor in the chart above: $0.15 per user a month at 11 to 100 users, $75 a year for 50 users and $555 for 500. It is the full Excalidraw editor (v0.18.1) as a macro on pages, with Mermaid, LaTeX math, Graphviz, Vega-Lite and WaveDrom diagrams written as text inside the same scene. It runs on Forge with no external calls, keeps the last 10 versions of each scene, and the page’s PDF and Word export includes the drawing.

It is not a draw.io replacement for BPMN or network diagrams with vendor stencils, it has no live co-editing and no AI. It comes in four listings that differ only in the first diagram type offered (Mermaid, UML, architecture, math); the Excalidraw family page compares them, and the Jira version shares the same scenes.

How we collected the data

• Which apps: Atlassian Marketplace REST API v2 on 4 November 2026, Confluence Cloud only: the “Charts & diagramming” category (219 listings) plus searches for “diagram”, “flowchart”, “whiteboard” and “uml”: 369 listings. 207 mention diagrams in their name or tagline. We sorted those by hand into editors, text-to-diagram apps, connectors and out of scope (Git include tools, image editors, analytics, charts from tables, 3D models), and kept the 118 with 10 or more installs. The 17 listings we could not place have 0 or 1 installs.
• Kind of free: the app’s payment model (“free” = free at any size); otherwise a $0 price on the 10-user tier, annual and monthly = free up to 10 users; anything else = paid.
• Prices: pricing/cloud/live, commercial user tiers, the cheapest edition. Annual prices for 50 and 500 users; monthly per-user prices from the same answer. Taxes and discounts are not included.
• Framework and release: versions/latest?hosting=cloud. A Forge app has a Forge app ID; a Connect app has none and is marked Connect.
• Listing quotes: the vendor’s own text in the same answer. “Not stated” means the listing does not say. We did not install the other vendors’ apps.
• Our four listings (Mermaid, UML, architecture and math Excalidraw apps) are one product and count as four of the 118.

The scripts and the full table of 118 apps are in our research notes; we will update this page when prices change.